How are the molecules moving in a cold glass of water compared to in a warm glass of water

7. what temperature is need to just dissolve 50 g of nh4cl in 75 g of water? '

How does kepler second law of planetary motion overthrow one of the basic beliefs of classical astronomy

Consider hydrogen in an excited state n = 5n=5 that emits photons to reach the ground state. there are various possible transitions other than straight to the ground state that can occur; for example, it can drop to the n = 3n=3 state followed by the n = 3n=3 to the ground state transition. which of the possible transitions will result in the emission of a photon in the visible region?